bfgminer devices not found

[joshck94]

Hi,
I am completely new to bitcoin and mining. I have a MacBook Pro Retina. I installed bfgminer via homebrew. When I run it, and log in to my pool, I get the error: Devices not found. Press "M" and "+". What do I do after that? Also, can somebody refer me to video tutorials regarding bitcoin? What is the purpose of a bank, etc?